<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <script src="https://cdn.bootcdn.net/ajax/libs/vue/2.6.14/vue.js"></script>
</head>
<body>
    <div id="app">
        <tom></tom>
        <jerry></jerry>
    </div>
</body>
<script>
 const eventBus = new Vue()
 Vue.component('tom',{
        data(){
            return {
                money: 1000
            }
        },
        template: `
            <div>
                <h3>tom-{{money}}</h3>
            </div>
        `,
        mounted() {
            eventBus.$on('pay',(val)=>{
                this.money-=val
            })
        }
    })
    Vue.component('jerry',{
        template: `
            <div>
                <h3>jerry</h3>
                <button @click="cost">cost</button>
            </div>
        `,
        methods: {
            cost(){
                eventBus.$emit('pay',100)
            }
        },
    })
    new Vue({
        data() {
            return {
            }
        },
        mounted() {
        },
        el: '#app'
    })

</script>
</html>